Biology HW
1. Define venation. Mention their types and give examples.
2. What are tendrils? Give examples.
3. Name some stem modifications.
4. Mention functions of stem.
Answers
Venation is the phenomenon of arrangement of veins in the lamina of the leaf surface. It is of three types, reticulate, parallel and furcate venation. In reticulate venation, veins form the network like structure. For example, leaves of dicot plants. In parallel venation, veins arise from the mid rib and run parallel.
They do not have a lamina or blade, but they can photosynthesize. Common examples of tendril-producing plants are the grape, members of the squash or melon family (Cucurbitaceae), and the sweet pea (Lathyrus odoratus)
The primary functions of the stem are to support the leaves; to conduct water and minerals to the leaves, where they can be converted into usable products by photosynthesis; and to transport these products from the leaves to other parts of the plant, including the roots.